Module 4 – Infection Prevention
- Differentiate between medical & surgical asepsis
- Demonstrate proper handwashing technique
- Develop understanding of Standard Precautions, Bloodborne Pathogen Standard, & types of Isolation
- Demonstrate understanding of Chain of Infection
What is an infection?
An infection is a disease that results from the invasion and growth of microbes in the body. It is a major safety and health hazard, and if unnoticed or left untreated can result in serious complications or death.
Infection control refers to the set of practices and procedures that individuals and facilities use to protect patients, residents, visitors, and staff from infection. Infection control is exceptionally important, and should be something that NAs always have at the forefront of their minds.
Microorganisms are extremely small beings such as bacteria and viruses. Microorganisms are everywhere; they are on every surface we touch, in the air we breathe, in various sources of water, and in our bodies. Microorganisms tend to prefer areas that are dark and damp.
A person’s microbiome is the ecosystem of bacteria that help us live. Human beings need our microbiome bacteria for gut health and other beneficial functions. Some people take pro-biotic medicine or foods to foster their microbiome.
Microorganisms that cause harm to people are called pathogens.
When pathogens, or dangerous microbes, are consistently exposed to anti-infection measures, they can adapt and become resistant. Antibiotic resistant bacteria are a serious problem in healthcare facilities.
TED Ed. (2014, August 7). What causes antibiotic resistance? – Kevin Wu [Video]. Youtube. https://www.youtube.com/watch?v=znnp-Ivj2ek
Infection control terminology
Infection control terminology usually fall under three general categories: words describing the body’s defense system, words describing microorganisms and infections, and words discussing asepsis [1] .
Words describing the body’s defense system:
- Antigens are foreign substances that initiate an immune response in the body. Antigens include pathogens, toxins, and any foreign substance that can be harmful to one’s body and ought to activate an immune response.
- Antibodies are proteins deployed by the body’s immune system that bind to and destroy antigens.
- Normal flora is a term for the normal microbes that live in certain areas of a healthy human body. For instance, the discussion above about the human microbiome is in reference to our normal flora.
Words describing microorganisms and infections:
- An object or space is contaminated when it contains potentially harmful microbes; contamination is the opposite of asepsis. Not all microorganisms are harmful; in fact, some are essential to human health. Non-harmful microorganisms are nonpathogenic.
- Contaminated surfaces should be cleaned and disinfected. One cleans a surface by applying products and friction to reduce the presence of microbes. Disinfecting a surface involves destroying the bacteria with chemicals like bleach, alcohol, and peroxide.
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An infection is an invasion of human tissue by pathogenic microbes. Most pathogens are combatable with disinfection techniques.
Spores are bacteria that are protected by a hard exterior shell, and are thus not killed with disinfectants
Sterilization techniques will be necessary to adequately combat spores and other hearty microbes that aren’t killed using standard disinfection.
- Pathogens will have varying degrees of virulence; virulence is a pathogen’s relative ability to cause disease.
Words describing techniques to combat infection:
- Sterilization refers to practices that destroy all microorganisms on a given surface using high temperatures, auto-clave pressure, and steam. “Sterile” is a difficult standard to reach. NAs will not be able to work in a completely sterile environment, but they should make sure that surfaces and hands are disinfected.
- Asepsis is the process of keeping surfaces and hands free of microorganisms. Aseptic practices are essential to safety and infection control. Part of maintaining asepsis is always applying Standard Precautions in the workplace.
- Standard Precautions assumes that all bodily fluids are contaminated. Anytime an NA comes into contact with a bodily fluid, they should automatically treat it as if they know for a fact that it contains dangerous pathogens. An example of a Standard Precaution is to always wear gloves when providing hands-on care, even if the person does not appear to be sick. This ensures that potential infection risks are immediately treated with a high degree of caution, and routinizes practices meant to minimize the spread of pathogens.
Communicable diseases
A communicable disease is a disease that can be spread from one person to another. Spread occurs through direct contact with the person, such as by being in physical contact or by breathing the same air as they do. Spread can also occur through indirect contact, such as by touching objects recently handled by the infected person [2] .
A contagious disease is a communicable disease that spreads easily and quickly. Non-communicable diseases are diseases that can’t spread from person to person, such as diabetes.
A body has a natural set of defense mechanisms to prevent and combat infections. The body’s skin, mucous membranes that protect our eyes, nose, and ears, and other defense mechanisms are in place to stop, trap, or remove pathogens to keep them from entering the body, or to kill them quickly once they do. Tools like fevers, the deployment of white blood cells, and other immune responses are to fight the infection once the pathogen has started reproducing within the person’s body.
If someone has a bacterial infection, they may be prescribed anti-biotics. Anti-biotics target some microorganisms. However, if anti-biotics are ineffective, it is likely that the person is suffering a viral infection, for which antibiotics won’t be an effective treatment.
Asepsis
NAs can work to minimize the spread of communicable diseases by practicing good asepsis technique. NAs should utilize medical asepsis techniques to minimize the risk of spreading infections from person to person, or from one part of a person’s body to another part of their body. It also works to reduce the risk of reinfection, which occurs when one person becomes infected multiple times with the same pathogen [3] .
Medical asepsis refers to the set of techniques healthcare staff use to keep a facility as clean and sanitized as possible. Techniques like regular handwashing, disinfecting surfaces, and wearing personal protective equipment (PPE) are all part of medical asepsis.
Medical asepsis cannot make an environment totally free of potential pathogens, let alone microorganisms. To make an object or area completely free of microorganisms involves sterilization, or the getting rid of all microorganisms, which is a technique used as part of surgical asepsis.
Surgical asepsis is different from medical asepsis in that it gets rid of all microorganisms, while medical asepsis gets rid of most microorganisms. Surgical asepsis is difficult to maintain, and requires that specific steps be taken. Sometimes procedures requiring sterile technique will require that NAs receive special training before they are allowed to assist.
Handwashing
Handwashing is essential to good asepsis technique. It is the most important thing you can do to practice infection control Washing one’s hands is something most people do regularly, but it is important to know how to do it well. Good handwashing will involve:
- Make sure to remove rings and jewelry prior to washing one’s hands to ensure a thorough clean. Items like rings and watches may also harbor bacteria and can be disinfected with hot soapy water.
- Rinse one’s hands under warm running water.
- Use antimicrobial soap and scrub one’s hands, including one’s fingernails and any other surface area where bacteria could accumulate. Scrubbing should last for at least 30 seconds – 1 minute.
- Rinse one’s hands under warm running water, and dry them.
Video by Allie Tiller is licensed under CC BY-NC 4.0
Infection control is part of the Big Three
Infection Control is the third pillar of the Big Three, in addition to Residents’ Rights and Safety, because NAs should always keep it in mind while they are working. It closely relates to the other two pillars of the Big Three.
Residents have a right to a comfortable and safe environment, so they also have a right to be free of infection to the extent that it is possible, and to have their infections promptly noticed and treated should they occur. Similarly, a resident who is regularly at a high-risk for potentially dangerous infections cannot be considered safe. Infection control is an essential aspect of providing effective care.
Noticing and treating infections
Noticing, treating, and minimizing the further spread of infections are parts of infection control. How can NAs observe and notice infections?
Inflammation occurs when tissue swells, and becomes discolored. Inflammation can occur because of damage to tissue, or as an immune response [4] .
There are many symptoms of inflammation beyond observable redness and swelling, such as:
- Mild fevers
- Pain, tenderness, and limited use in the impacted part of the body
- Nausea
- General aches and discomfort
The above symptoms may indicate an immune response to the presence of infection.
The presence of infection symptoms
Everybody responds to pathogens differently, and the symptoms of a person’s infection and infection response can vary depending on multiple factors.
The virulence of microbes can vary. Virulence is a word that refers to how harmful different pathogens are. The more virulent and highly concentrated a pathogen is, the more likely it is to produce a harmful infection.
The overall health of the person and the general condition of their immune system impacts their susceptibility to infection. Proper nutrition and hydration are necessary for maintaining a robust immune system. Age, genes, and comorbidities are also relevant factors.
Emotional stress and emotional or physical exhaustion can have significant impacts on the immune system. It is important that residents do things that they enjoy, and find engaging and relaxing. This has a real impact on the immune system’s ability to fight off infections.
Symptoms of infection
The signs and symptoms of infection vary widely. They include:
- fever
- chills
- increased pulse and respiratory rate
- pain and tenderness
- fatigue
- loss of appetite
- nausea
- vomiting
- diarrhea
- joint pain
- confusion
- rashes
- sores on mucous membranes
- redness or swelling
- discharge from an infected area
- heat or warmth emanating from a body part
- the limited use of a body part
- headaches
Report any of these symptoms to the nurse and record them in the chart.
Some different kinds of infection
A localized infection is an infection that impacts a specific area, such as an infected wound. Localized infections can sometimes spread to other parts of the body. Microorganisms that are normal flora in one area of the body may be pathogenic in another.
A generalized infection is an infection that broadly affects a specific area, such as pneumonia, a rash all over the body, pink eye in both eyes, or an infection in the brain.
A systemic infection is an infection that has entered the blood stream and is therefore being carried throughout the body system; septicemia, or sepsis, is an example of this type of infection.
Healthcare-Acquired Infections (HAIs)
Healthcare-acquired infections (HAIs) are infections that develop while a person is being cared for in a healthcare facility or home-care setting. HAIs are common and dangerous, with roughly 1.7 millions and infections and 99,000 associated deaths each year.
32% of HAIs are urinary tract infections (UTIs). Residents or patients that use urinary catheters are at heightened risk for UTIs. NAs can help minimize the risk of UTIs by not leaving urinary catheters in place for extended periods of time, and by keeping the catheter and surrounding area clean. Catheter-associated urinary tract infections have the acronym CAUTI.
22% of HAIs are surgical site infections. NAs can help minimize surgical site infections by observing the site closely and closely following medical sepsis when caring for the site as it heals [5] . Other HAIS include developing pneumonia by using a ventilator, and some blood infections that result from surgeries or medical equipment.
The CDC now estimates that as many of one-third of US hospitals fail to follow the CDC’s guidelines for handwashing and other basic infection control measures, even though universal strict adherence to clean-hand policies could prevent roughly 20,000 HAI attributed deaths each year [6] .
Healthcare facilities should be a place of care and healing, and it is devastating and ironic when the care someone receives results in the infection that kills them.
Multi-drug resistant organisms (MDROs)
Some HAIs are caused by multidrug-resistant organisms (MDROs), which are microbes capable of resisting the effects of antibiotics. This occurs when an organism is capable of adapting quickly in response to antibiotic treatment; rather than the antibiotic getting rid of the organism, the organism adapts so the antibiotic is no longer effective.
MDROs are rampant in healthcare facilities, and pose serious health risks to patients and residents. Three MDROs NAs should be familiar with are MRSA, c. diff., and VRE [7] .
MRSA
MRSA, pronounced mer-za, is an acronym for methicillin-resistant Staphylococcus aureus .
MRSA is capable of withstanding the effects of the powerful antibiotic methicillin.
- MRSA usually manifests as a skin infection, but can also infect surgical wounds, the bloodstream, lungs, or urinary tract. It is usually either a generalized or systemic infection.
- MRSA is spread by direct contact; since the bacteria lives on our skin, touch tends to be the medium of contagion. People can contract MRSA through skin to skin contact with an infected person or by touching a contaminated object.
- MRSA changes and mutates all the time to remain resistant to antibiotics. The people most susceptible to severe MRSA are the elderly, people with weakened or compromised immune systems, and people who use tubing and implanted devices. Tubing and implants increase risk of severe MRSA because they give the bacteria a clear portal of entry into the bloodstream.
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Treatment and guidelines
: A person with MRSA will be treated with an antibiotic therapy. When caring for a person with MRSA, NAs should make sure to keep any drainage from the infection contained and not let it spread to other areas of the skin or to surfaces or objects in the room.
Use a 1:10 bleach solution to wipe contaminated surfaces.
- Exceptional hand hygiene is required, including the use of gloves when touching a patient or contaminated surfaces, and a gown when there is potential for any contamination of one’s clothing. A person infected with MRSA should not share any of their items with anyone.
C. diff
Clostridium difficile , or diff for short, is a bacterial pathogen that can develop when someone is taking anti-biotics. C.diff is a naturally occurring gut bacteria that is usually kept in balance by other bacteria in the gut microbiome. When someone takes an antibiotic that throws the gut biome out of balance, concentrations of c.diff can reach dangerous levels and cause serious illness.
According to the CDC, likelihood of reinfection with c.diff is high, and one in eleven people over the age of sixty-five who contract c.diff will die within one month [8] .
C.diff is contagious. Wash your hands often, shower after your shift every day, and do not use a shared restroom while experiencing diarrhea. C.diff spores can lie dormant on a surface for five months and are not killed by alcohol hand sanitizers. Soap and water are the best defense against c.diff.
Symptoms of c.diff include:
- frequent diarrhea
- fever
- stomach pain
- loss of appetite
- nausea
If these symptoms are observed in a patient or in oneself, alert a nurse immediately.
Treatment for c.diff may include a fecal microbiota transplant (FMT). A FMT involves transplanting stool from a healthy individual into the colon of the person with the infection. This counteracts the c.diff by reintroducing necessary normal flora back into the colon.
VRE
VRE is the acronym for Vancomycin resistant Enterococcus . Enterococcus is a species of bacteria that are part of the intestinal tract’s normal flora. VRE can enter the bloodstream and cause meningitis, pneumonia, or an infection in the heart.
The symptoms of VRE manifest differently depending on the location of the infection. General symptoms of VRE include:
- drainage from a would
- fever
- chills
- fatigue
- redness and swelling
VRE is spread via direct contact between people or between a person and a contaminated object. NAs can help prevent the spread of VRE by practicing meticulous hand hygiene and disinfecting surfaces with a bleach solution . NAs should wear protective items like gloves and gowns whenever they are at risk of contamination.
The Chain of Infection
The Chain of Infection is a way of thinking about how disease spreads from one person to the next. It is a sequential loop that starts with a harmful bacteria and ends with a person’s infection; the cycle the starts again, since the infection will allow the pathogen to proliferate and spread.
The chain of infection progresses: 1. Causative agent > 2. Reservoir > 3. Portal of exit > 4. Mode of transmission > 5. Portal of Entry > 6. Susceptible host
Image by Genieieiop, CC BY-SA 4.0 ,
- Causative agent: the pathogenic microbe that infects a person and causes illness. Causative agents could be bacteria, fungi, or viruses.
- Reservoir: surface or host where causative agent lives. The reservoir for a pathogenic microbe could be the surface of a piece of equipment or furniture, or in the food, water, and air. Animals and humans can also be reservoirs for pathogens. Microbes tend to prefer warm and oxygen-rich environments, and tend to grow better at body temperature. Many are capable of surviving on hard surfaces and in linen. Treat contaminated surfaces and linen with care.
- Portal of exit: the pathogen’s means of exiting the reservoir. In the case of human or animal reservoirs, portals of exit can include things like mucus, waste, spit, breath, and blood. A portal of entry is a pathogen’s means of entering a new host.
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Mode of transmission: the means the microbe uses to travel from a reservoir to a host, or from one host to another host. Different pathogens travel via different modes of transmission; some require contact, while others may be airborne or travel through the different medium of respiratory droplets.
- Vector transmission of a pathogen occurs when an infectious agent transfers a pathogen to another host, while vehicle transmission occurs when a pathogen enters a host from a substance or surface.
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Host: a hospitable environment for a pathogen to reproduce in, and a launchpad from which it can travel and infect other hosts. A human body can spread pathogens more efficiently than pathogens can spread themselves by interacting dynamically with their environment (breathing, coughing, touching things).
- People who are immune-compromised, elderly, or experiencing a health condition (whether chronic or acute) are at increased risk of becoming a host to an infection.
- People who live in nursing homes are at an increased risk of infection because of the higher amount of pathogenic microbes contained in the facility; because of the high concentration of people and microbes in such facilities residents are more likely to come into contact with pathogens, and are less likely to be able to successfully defend themselves against the infection.
Try out this interactive infection control game: https://www.wisc-online.com/learn/career-clusters/health-science/nur1603/chain-of-infection
Breaking the chain
There are many different things healthcare staff can do to “break the chain” of infection. When we break the chain, it means we take steps to interrupt the spread of pathogens; if one link in the chain is broken, it can prevent someone from contracting (and then spreading) what might otherwise be a harmful infection.
Here are some basic precautions that facilities and facility staff should implement:
- Wash hands before and after every care task
- Use personal protective equipment (PPE)
- Deploy isolation techniques when a person develops an infection
- Identify the infection and the type of microbe that causes it
- Facility staff should keep themselves generally healthy; overall health in the form of nutrition, hydration, sleep, and exercise is important for maintaining a robust immune system.
- Cleaning and disinfecting all equipment
- Always use aseptic technique
- Make sure residences have good airflow
- Keep hands moisturized so they do not crack and create a portal of entry
Standard Precautions
The Center for Disease Control (CDC) is an organization in the federal government that performs a variety of public health functions. The CDC researches and publishes information on diseases and issues guidelines on how the public should respond to disease. The CDC has an infection-prevention system used in healthcare facilities meant to minimize the risk of infections spreading [9] .
The CDC has guidelines on the kinds of precautionary measures that must be taken to prevent infection. The two levels of precautions are Standard Precautions and Transmission-based Precautions.
Standard Precautions are a set of precautions that healthcare staff use all of the time, with all of their patients or residents. The basic idea behind Standard Precautions is to always treat blood and other bodily fluids, nonintact skin, and mucus membranes (eyes, nostrils, mouth, sex organs, and rectum) as though one is certain they are infected.
Gloves : Standard Precautions require the use of gloves whenever there is the possibility of coming into contact with bodily fluids, nonintact skin or other tissues, and mucus membranes.
- Always wash your hands immediately before and after putting on gloves; only use a pair of gloves for the procedure, and then quickly remove them.

- Wear gloves whenever using objects like razor blades, needles, or anything else that might cause a person to bleed.
PPE : Other personal protective equipment (PPE) such as gowns, face shields, face masks, protective goggles may be required in addition to gloves if staff members may get bodily fluids on their clothes or face while administering care.
Image by National Institutes of Health (NIH) is licensed under CC BY-NC 2.0 .
Bloodborne Pathogen Standard : An important aspect of Standard Precautions is to also follow OSHA’s Bloodborne Pathogen Standard. As part of the Bloodborne Pathogen Standard, employers are required to keep labeled “Hazard” bins for needles and sharps, as well as to provide employees with training and information on how to avoid an accidental needle stick, and other aspects of keeping oneself safe from bloodborne infections like HIV and Hepatitis B and C. As part of OSHA’s legBloodborne Pathogen Standardislation, employers must teach employees how to handle bloodborne pathogen exposure, maintain an exposure control plan, universally implement Standard Precautions, and utilize PPE.
- Biohazards: A biohazard is any substance or object that carries a risk of infection, especially infection with a bloodborne illness. NAs must always put needles and other sharps into the labeled biohazard bin.  NAs should always follow their facility policies on waste disposal, and should dispose of hazardous waste, or potentially contaminated objects, quickly in accordance with facility policies.
- If an employee has an exposure to blood or another bodily fluid, also called an exposure incident, they will have to fill out an exposure report form and follow up on any necessary medical tests.
Montana State Fund. (2020, March 2). Health care bloodborne pathogen safety [Video].  They are precautions meant to prevent the transmission of illness once it is present and use isolation and heightened anti-infection techniques to limit is spread.
Transmission-Based Precautions require the use of specific pieces of PPE depending on the kind of pathogen or illness the person is exhibiting. Nurses will tell the NA what kind of PPE each person’s transmission precautions require; some facilities have signs on patients’ doors that describe the transmission precaution and PPE required.
All Transmission-Based Precautions also include Standard Precautions and washing one’s hands before entering and after leaving the room.
The three different kinds of Transmission-Based Precautions are airborne, droplet, and contact precautions.
- Airborne : Airborne Precautions are put in place for people who may spread pathogens that are expelled into the air and may remain there long enough to be inhaled by or land on a new person. Airborne infection isolation rooms (AIIR) are necessary for people under airborne precautions; AIIRs have increased air circulation and filtration to dispose of infected air quickly and to make sure no other parts of the facility are infected. Staff must wear a N95 respirator mask, and keep the door and windows closed at all times.
- Droplet : Droplet precautions are applied for people with pathogens that transmit through droplets of moisture that are expelled and either remain in the air or settle on surfaces. Droplet precautions require a respiratory mask be worn in the room at all times. Droplet precautions may require a restriction on visitors.
- Contact : Contact precautions are used when a person has an infection that is spread by direct or indirect contact. Contact precautions require the use of gloves and a gown. People requiring contact precautions cannot share equipment or linens with others; if two people must share a piece of equipment then it needs to be thoroughly disinfected between each use.
Isolation
All transmission-based precautions include isolating the person. If a person needs to be isolated due to transmission-based precautions, NAs should be aware of the negative impact that isolation can have on a person’s wellbeing, especially when it comes to their psychosocial needs. The experience can be taxing on a person.
Isolation makes somebody more vulnerable to infringements on their rights as patients and residents. NAs should always recognize that residents in isolation are at greater risk of having their rights infringed upon; when someone requires isolation, never let their call light go unattended and make sure to check in on them frequently to provide care and moments of human interaction.
Fronheiser, A. (2017, June 15). Transmission based precautions [Video]. Youtube. https://www.youtube.com/watch?v=qL-Eyq62-zc
PPE
The CDC and OSHA recommend the use of personal protective equipment (PPE) for Standard Precautions, the Bloodborne Pathogen Standard, and for Transmission-Based Precautions. PPE is used to protect care team members from acquiring any of the communicable diseases that they work hard to treat. Some different kinds of PPE are gloves, gowns, goggles and face shields, and masks and respirators.
If a patient requires a specific piece of PPE the nurse will usually say something, but it is important for NAs to be able to identify risk levels themselves and be able to apply the appropriate response. Different conditions will require different pieces of PPE – for instance, a person with pneumonia will require different kinds of PPE than a person with chicken pox.
Different isolation precautions will require different kinds of PPE. Discuss such precautions with the nurse, and when in doubt always ask. PPE protects both its wearer and every person they interact with afterwards; if you think it might be necessary, then it is. Employers are obligated to provide staff with PPE.
What PPE would you need when: transporting someone in a wheelchair? Responding to an emergency involving spurting blood? Cleaning a patient who had experienced diarrhea? Taking someone’s vital signs?  While emptying a catheter drainage bag? Consider the kinds of risk these activities put someone in, and the PPE someone could use to protect themselves. Write for 5 minutes, and discuss your response with a friend or classmate.
Donning and Doffing : When donning, or putting on, a full set of PPE, one should go in the order of gown, then the mask/respirator, then the goggles or face shield, and finally the gloves. When doffing, or removing, PPE one should go in the order of gloves, then goggles/face shield, then gown, and mask last.
Registered Nurse RN. (2020, May 29). PPE training video: Donning and doffing PPE nursing skill [Video]. Youtube. https://www.youtube.com/watch?v=iwvnA_b9Q8Y
Disposing of waste
Healthcare teams use many objects that, after their use, need to be disposed of. Always practice Standard Precautions while handling contaminated material. However, some material is considered more contaminated or more dangerous than others.
Healthcare facilities use a two-bag system for disposing of waste.  Non-biohazardous waste is disposed of in clear waste bags.
Image by stonebird is licensed under CC BY-NC-SA 2.0 .
Non-biohazardous waste is still considered contaminated or “dirty.” The items that can be disposed of in clear waste bags (non-biohazardous) include household waste such as food and food containers, paper products, non-bloody PPE, and IV bags.
Bio-hazardous materials require a bit more of a multi-step process to be properly disposed of. Because even the outside of the bag of biohazards is considered contaminated, biohazardous materials need to be double-bagged.
The double-bagging process involves one person who bags the material inside the room and one who stands outside with a red bag, or a labeled biohazard bag, folded over their hands. The bag from inside the room is placed inside the red bag, and is then transferred to the dirty utility room or the hazardous waste container.
Key Takeaways
- Infection control is part of the Big Three. NAs should think critically about applying infection control measures in everything they do.
- Medical asepsis is used all the time, and refers to techniques like regular handwashing and disinfecting surfaces and equipment. Surgical asepsis is used to remove all microorganisms from a surface; surgical asepsis often deploys sterile technique, for which NAs will need special training to perform.
- The Chain of Infection refers to the cycle of pathogens from living on a surface or in a host, to entering a new host, to creating an infection and spreading through the host’s activities. Healthcare staff are responsible for breaking the chain of infection.
- Standard Precautions and the Bloodborne Pathogen Standard should be applied all the time; the gist of these frameworks involves considering any and all bodily fluids as contaminated, and protecting yourself accordingly. During transmission-based precautions, a resident may be placed in either airborne, droplet, or contact isolation; different kinds of isolation require different kinds of PPE, though they all require heightened caution. Isolation is hard on a person; watch out for the negative psychosocial impacts of isolation precautions.
Comprehension Questions
1) What sort of environment is best for pathogens to live and reproduce in?
a. An icy area
b.  A damp and dark area
d. A hot, dry, and sunny area
2) Respond to the following sentences with T (true) or F (false).
____ Pathogens are microbes that can cause infection.
____ Antibodies are foreign substances that activate an immune response.
____ A person’s gut biome is one example of their normal flora.
____ If a resident’s napkin falls off their meal tray and onto the floor, it is contaminated.
____ Medical asepsis requires sterile technique.
3) Medical asepsis includes which of the following? Select all that apply.
a. Regular handwashing
b. Isolation
d. Standard Precautions
e. The Bloodborne Pathogen Standard
4) Which of the following are symptoms of an infection?
a. Inflammation and redness in an area
b. Bruising
c. Mild fever
d. Confusion
e. Changes in personality
f. Headaches
g. Dry skin
5) Respond to the following sentences with T (true) or F (false).
____ A systemic infection only impacts a specific area of the body.
____ An infected wound is an example of a localized infection.
____ Healthcare-acquired infections (HAIs) are serious problems in medical facilities.
____ Normal flora are never harmful to human bodies.
____ MDROs are pathogens that develop resistance to drugs and become even more dangerous.
6) Which of the following PPE is required for Droplet Precautions?
a. Frequent hand hygiene
b. An Airborne Infection Isolation Room
c. A mask or respirator
d. A gown
7) Please put the links of the Chain of Infection in order.
8) Why is it important for NAs to spend extra time with people in isolation rooms due to infection precautions?
a. Because the more time exposed patients spend with healthy staff, the less likely they are to become sick.
b. NAs need practice being around sick people.
c. Isolation makes it difficult for someone to meet their psychosocial needs; NAs can offer some human connection when visitors are otherwise restricted.
e.
9) What are some techniques NAs can use to break the Chain of Infection? Select all that apply.
a. Keep themselves in good health so they have a robust immune system.
b. Use regular hand hygiene.
c. Treat sick patients kindly so they are motivated to get better.
d. Closely observe residents and patients for signs of illness and infection so they can be caught early.
e.
10) Respond to the following sentences with T (true) or F (false).
____ MRSA requires airborne transmission precautions.
____ VRE is sometimes treated using a fecal microbiota transplant.
____ C. diff is an MDRO that is usually part of the human gut biome’s normal flora.
____ Only nurses and doctors are responsible for breaking the Chain of Infection, because it requires specific training.
____ Standard Precautions are practiced as a way to make breaking the Chain of Infection a habit for all healthcare staff.
11) Imagine that you see a fellow NA administer a routine injection for a resident. You notice that they do not use gloves to administer the injection, and then set the needle on a countertop while performing some more care tasks. What safety precaution does this violate?
12) Why is Infection Control included as part of the Big Three? What do Infection Control measures have to do with Resident Rights and Safety? Try to come up with at least two connections for both Resident Rights and Safety.
References
- Glossary; Infection prevention terms. (2011). https://www.vdh.virginia.gov/content/uploads/sites/13/2016/03/Glossary.pdf ↵
- Staff Writer. (2023, February 5). Standard Precautions, Transmission Based, Surgical Asepsis: NCLEX-RN. RegisteredNursing.org. https://www.registerednursing.org/nclex/standard-precautions-transmission-based-surgical-asepsis/ ↵
- Staff Writer. (2023, February 5). Standard Precautions, Transmission Based, Surgical Asepsis: NCLEX-RN. RegisteredNursing.org. https://www.registerednursing.org/nclex/standard-precautions-transmission-based-surgical-asepsis/ ↵
- Sorrentino, S. A., & Remmert, L. N. (2019). Mosby's essentials for nursing assistants (6th ed.), Chapter 13. Elsevier. ↵
- Healthcare-Acquired infections. (n.d.). Patient Care Link. Retrieved April 27, 2023, from https://www.patientcarelink.org/improving-patient-care/healthcare-acquired-infections-hais/ ↵
- CDC. (2021). Infrastructure and routine practices. https://www.cdc.gov/infectioncontrol/guidelines/healthcare-personnel/infrastructure.html ↵
- Dugan, D. (2020). Nursing assisting: A foundation in caregiving (5th ed.), Chapter 6. Hartman. ↵
- CDC. (2021). C. diff (Clostridioides difficile). https://www.cdc.gov/cdiff/index.html ↵
- Staff Writer. (2023, February 5). Standard Precautions, Transmission Based, Surgical Asepsis: NCLEX-RN. RegisteredNursing.org. https://www.registerednursing.org/nclex/standard-precautions-transmission-based-surgical-asepsis/ ↵


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A transformer is a device that connects two electrical circuits through a shared magnetic field. Transformers are used in impedance transformation, voltage level conversion, circuit isolation, conversion between single-ended and differential signal modes, and other applications. 1 The underlying electromagnetic principle is Faraday’s Law – in particular, transformer emf.
The essential features of a transformer can be derived from the simple experiment shown in Figures \(\PageIndex{1}\) and \(\PageIndex{2}\). In this experiment, two coils are arranged along a common axis. The winding pitch is small, so that all magnetic field lines pass through the length of the coil, and no lines pass between the windings. To further contain the magnetic field, we assume both coils are wound on the same core, consisting of some material exhibiting high permeability. The upper coil has \(N_1\) turns and the lower coil has \(N_2\) turns.
Figure \(\PageIndex{1}\): Part I of an experiment demonstrating the linking of electric circuits using a transformer.Figure \(\PageIndex{2}\): Part II of an experiment demonstrating the linking of electric circuits using a transformer.
In Part I of this experiment (Figure \(\PageIndex{1}\)), the upper coil is connected to a sinusoidally-varying voltage source \(V_1^{(1)}\) in which the subscript refers to the coil and the superscript refers to “Part I” of this experiment. The voltage source creates a current in the coil, which in turn creates a time-varying magnetic field \({\bf B}\) in the core.
The lower coil has \(N_2\) turns wound in the opposite direction and is open-circuited. Given the closely-spaced windings and use of a high-permeability core, we assume that the magnetic field within the lower coil is equal to \({\bf B}\) generated in the upper coil. The potential induced in the lower coil is \(V_2^{(1)}\) with reference polarity indicated in the figure. From Faraday’s Law we have
\[V_2^{(1)} = - N_2 \frac{\partial}{\partial t} \Phi_2 \label{m0031_ePartIa} \]
where \(\Phi_2\) is the flux through a single turn of the lower coil. Thus: \[V_2^{(1)} = -N_2 \frac{\partial}{\partial t} \int_{\mathcal{S}} { {\bf B} \cdot (-\hat{\bf z}ds) } \label{m0031_ePartIb} \] Note that the direction of \(d{\bf s}=-\hat{\bf z}ds\) is determined by the polarity we have chosen for \(V_2^{(1)}\).
In Part II of the experiment (Figure \(\PageIndex{2}\)), we make changes as follows. We apply a voltage \(V_2^{(2)}\) to the lower coil and open-circuit the upper coil. Further, we adjust \(V_2^{(2)}\) such that the induced magnetic flux density is again \({\bf B}\) – that is, equal to the field in Part I of the experiment. Now we have \[V_1^{(2)} = - N_1 \frac{\partial}{\partial t} \Phi_1 \nonumber \]
which is
\[V_1^{(2)} = -N_1 \frac{\partial}{\partial t} \int_{\mathcal{S}} { {\bf B} \cdot (+\hat{\bf z}ds) } \nonumber \]
For reasons that will become apparent in a moment, let’s shift the leading minus sign into the integral. We then have
\[V_1^{(2)} = +N_1 \frac{\partial}{\partial t} \int_{\mathcal{S}} { {\bf B} \cdot (-\hat{\bf z}ds) } \nonumber \]
Comparing this to Equations \ref{m0031_ePartIa} and \ref{m0031_ePartIb}, we see that we may rewrite this in terms of the flux in the lower coil in Part I of the experiment:
\[V_1^{(2)} = +N_1 \frac{\partial}{\partial t} \Phi_2 \nonumber \]
In fact, we can express this in terms of the potential in Part I of the experiment:
\[\begin{align} V_1^{(2)} &= \left(-\frac{N_1}{N_2}\right) \left(-N_2 \frac{\partial}{\partial t} \Phi_2 \right) \nonumber \\ &= \left(-\frac{N_1}{N_2}\right) V_2^{(1)} \end{align} \nonumber \]
We have found that the potential in the upper coil in Part II is related in a simple way to the potential in the lower coil in Part I of the experiment. If we had done Part II first, we would have obtained the same result but with the superscripts swapped. Therefore, it must be generally true – regardless of the arrangement of terminations – that
\[V_1 = -\frac{N_1}{N_2}V_2 \nonumber \]
This expression should be familiar from elementary circuit theory – except possibly for the minus sign. The minus sign is a consequence of the fact that the coils are wound in opposite directions. We can make the above expression a little more general as follows: \[\boxed{ \frac{V_1}{V_2} = p\frac{N_1}{N_2} } \label{m0031_eTL} \] where \(p\) is defined to \(+1\) when the coils are wound in the same direction and \(-1\) when coils are wound in opposite directions. (It is an excellent exercise to confirm that this is true by repeating the above analysis with winding direction changed for either the upper or lower coil, for which \(p\) will then turn out to be \(+1\).) This is the “transformer law” of basic electric circuit theory, from which all other characteristics of transformers as two-port circuit devices can be obtained (See Section 8.6 for follow-up on that). Summarizing:
The ratio of coil voltages in an ideal transformer is equal to the ratio of turns with sign determined by the relative directions of the windings, per Equation \ref{m0031_eTL}.
A more familiar transformer design is shown in Figure \(\PageIndex{3}\) – coils wound on a toroidal core as opposed to a cylindrical core. Why do this? This arrangement confines the magnetic field linking the two coils to the core, as opposed to allowing field lines to extend beyond the device. This confinement is important in order to prevent fields originating outside the transformer from interfering with the magnetic field linking the coils, which would lead to electromagnetic interference (EMI) and electromagnetic compatibility (EMC) problems. The principle of operation is in all other respects the same.
Figure \(\PageIndex{3}\): Transformer implemented as coils sharing a toroidal core. Here \(p = +1\). (CC BY SA 3.0; BillC)- See “Additional Reading” at the end of this section for more on these applications.↩


17.1: Newtonian Formulation
Classical mechanics as formulated by Isaac Newton (1652-1727) is all about forces. Newtonian mechanics works well for problems where we know the forces and have a reasonable coordinate system. In these cases, the net force acting on a system at position \(q\) is simply:
\[ F_{\mathrm{net}}(q) = m\ddot{q} = m \dfrac{d^2 q}{dt^2}. \label{18.1.1} \]
Or, in other words, if we know the net force acting on a system of mass \(m\) at position \(q\) at some time \(t_0\), we can use Equation \ref{18.1.1} to calculate the position of the system at any future (or past) time. We have completely determined the dynamical evolution of the system.\(^1\)
A ball of mass \(m\) is at ground level and tossed straight up from an initial position \(q_0\) with an initial velocity \(\dot{q}_0\) and subject to gravity alone. Calculate the equation of motion for the ball (i.e. where is the ball going to be after some time \(t\)?). 2
- Answer
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Since the only force acting on the ball is gravity, we can use the equation for the gravitational force to start our derivation:
\[ F_{\mathrm{gravity}}=-mG, \nonumber \]
with \(G\) the usual gravitational constant (\(G=9.8\; \mathrm{m}/\mathrm{s}^{2}\)). We can then replace this expression into Equation \ref{18.1.1}, to obtain:
\[ \begin{aligned} -mG &=m \ddot{q} \\ -G &=\ddot{q} \\ -G &=\dfrac{d\dot{q}}{dt}, \\ \end{aligned} \nonumber \]
which can then be integrated with respect to time, to obtain:
\[ \begin{aligned} -G\int_{t=0}^{t} dt &=\int_{\dot{q}_0}^{\dot{q}} d\dot{q}\\ \dot{q} &= \dot{q}_0-Gt\\ \dfrac{dq}{dt} &= \dot{q}_0-Gt,\\ \end{aligned} \nonumber \]
which can be further integrated with respect to time, to give:
\[ \begin{aligned} \int_{q_0}^{q} dq &= \int_{t=0}^{t} \dot{q}_0 dt -G \int_{t=0}^{t}tdt\\ q &= q_0 + \dot{q}_0 t -\dfrac{1}{2}Gt^2. \end{aligned} \nonumber \]
This final equation is the equation of motion for the ball, from which we can calculate the position of the ball at any time \(t\). Notice how the equation of motion does not depend on the mass of the ball!
How much time will a ball ejected from a height of \(1 \;\mathrm{m}\) at an initial velocity of \(10 \;\mathrm{m/s}\) take to hit the floor?
- Answer
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We can use the equation of motion obtained above to solve this problem, and obtain for this specific case \(t\simeq 2.12 \;\mathrm{s}\). 3
The formula of Newtonian mechanics are not the only one we can use to solve a problem in classical mechanics. We have at least two other equivalent approaches to the same problem that might end up being more useful in certain situations.
- Notice that, in principle, \(q\) \(\in\) \(\mathbb{R}^{n}\) is the position vector and \(\dot{q}\) \(\in\) \(\mathbb{R}^{n}\) is the velocity vector. As such, all the equation of classical mechanics are vector equation, and not just simple numerical equation, as we present them here! For our purposes, we can restrict ourselves to a 1-dimensional space, hence forgetting the complications of vector algebra.
- This example is based on Rhett Allain’s blog post that can be found (here)[ https://rhettallain.com/2018/10/31/classical-mechanics-newtonian-lagrangian-and-hamiltonian/ ]
- Can you write a python program to do this calculation?


1.3: Planning for Success
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Introduction
Now that you know more about how people learn, you want to think about how to apply it to your own learning. How do you learn best? How can you use that information to be a more successful student?
To learn more about your strengths and weaknesses as a learner, you can complete various inventories related to learning styles, attitudes, and motivations. For some of us, it’s even harder to recognize our strengths than to recognize our weaknesses. Maybe we don’t want to brag. Maybe we’re attached to a poor self-image. The reasons don’t matter. Part of becoming a successful student means telling the truth about our positive qualities, too.
Remember that weaknesses are often strengths taken to an extreme. The student who carefully revises her writing can make significant improvements in a term paper. If she revises too much and hands in the paper late, though, her grade might suffer. Any success strategy carried too far can backfire.
Figuring out how you learn and how to use that information is an important step in becoming a master student. You explored the various learning theories, and during this module, you will learn more about how to develop strategies to enhance your learning.
Planning for Success: Taking the First Steps
To succeed in school, tell the truth about what kind of student you are and what kind of student you want to become. Success starts with telling the truth about what is working—and what is not working—in our lives right now. When we acknowledge our strengths, we gain an accurate picture of what we can accomplish. When we admit that we have a problem, we are free to find a solution. Ignoring the truth, on the other hand, can lead to problems that stick around for decades.
Let’s be truthful: It’s not fun to admit our weaknesses. Many of us would approach a frank evaluation of ourselves about as enthusiastically as we would greet a phone call from the bank about an overdrawn account.
There is another way to think about self-evaluations. If we could see them as opportunities to solve problems and take charge of our lives, we might welcome them. Believe it or not, we can begin working with our list of weaknesses by celebrating them.
Whether written or verbal, the ways that we express our self-analysis are more powerful when they are specific. For example, if you want to improve your note-taking skills, you might write, “I am an awful note taker,” but it would be more effective to write, “I can’t read 80 percent of the notes I took in Introduction to Psychology last week, and I have no idea what was important in that class.”
Be just as specific about what you plan to achieve. You might declare, “I want to take legible notes that help me predict what questions will be on the final exam.”
As you use the results of your self-analysis, you might feel surprised at what you discover. Just tell the truth about it. The truth has power.
It is important for you to discover and acknowledge your own strengths as well as your areas for improvement. For many students, this is difficult to do. Some people suggest that looking at areas for improvement means focusing on personal weaknesses. They view it as a negative approach that runs counter to positive thinking. Positive thinking is a great technique. So is telling the truth, especially when we see the whole picture—the negative aspects as well as the positive ones.
To start your self-analysis, use the following suggestions as a guideline.
Be specific. It is not effective to write, “I can improve my communication skills.” Of course you can. Instead, write down precisely what you can do to improve your communication skills. For example, “I can spend more time really listening while the other person is talking, instead of thinking about what I’m going to say next.”
Be self-aware. Look beyond the classroom. What goes on outside school often has the greatest impact on your ability to be an effective student. Consider your strengths and weaknesses that you may think have nothing to do with school.
Be courageous. Self-analysis calls for an important master student quality—courage. It is a waste of time to do this if this is done half-heartedly. Be willing to take risks. You might open a door that reveals a part of yourself that you didn’t want to admit was there.
Strengths
Examine your strengths by thinking about the following:
- One area where I show strong skills is ...
- Another area of strength is ...
Goals
Think about the areas you need to improve and make them your goals:
- The area in which I most want to improve is ...
- It is also important for me to get better at ...
- I want to concentrate on improving these areas because ...
- To meet my goals for improvement, I intend to ...
Planning for Success: Self-Analysis Using Discovery Statements
One way of thinking about success or failure is to focus on habits. Behaviors such as ignoring reading assignments or skipping class might be habits that lead to outcomes that could not be avoided—including dropping out of school. In the same way, behaviors such as completing assignments and attending class might lead to the outcome of getting an A.
When you confront a behavior that undermines your goals or creates a circumstance that you don’t want, consider a new attitude: That behavior is just a habit. And it can be changed.
Thinking about ourselves as creatures of habit actually gives us power. In that way, we are not faced with the monumental task of changing our very nature. Rather, we can take on the doable job of changing our habits. One consistent change in behavior that seems insignificant at first can have effects that ripple throughout your life. Following are ways to test this idea for yourself.
One way to put your self-analysis into action is by journaling about your behaviors and habits and then creating discovery and intention statements.
Discovery Statements
Through discovery statements , you gain awareness of “where you are.” These statements are a record of what you are learning about yourself as a student—both your strengths and your weaknesses. Discovery statements can also be declarations of your goals, descriptions of your attitudes, statements of your feelings, transcripts of your thoughts, and chronicles of your behaviors.
Sometimes, discovery statements chronicle an a-ha! moment—a flash of insight that results when you connect a new idea with your previous experiences, preferred styles of learning, or both. Perhaps a solution to a long-standing problem suddenly occurs to you. Or a life-changing insight wells up from the deepest recesses of your mind. Don’t let such moments disappear. Capture them in discovery statements.
Record the specifics about your thoughts, feelings, and behavior. Notice your thoughts, observe your actions, and record them accurately. Get the facts. If you spent 90 minutes to checking your social media feed instead of reading your anatomy text, write about it. Include details.
Use discomfort as a signal. When you approach a daunting task, such as a difficult math problem, notice your physical sensations. Feeling uncomfortable, bored, or tired might be a signal that you’re about to do valuable work. Stick with it. Write about it. Tell yourself you can handle the discomfort just a little bit longer. You will be rewarded with a new insight.
Suspend judgment. When you are discovering yourself, be gentle. Suspend self-judgment. If you continually judge your behaviors as “bad” or “stupid,” your mind will quit making discoveries. For your own benefit, be kind to yourself.
Tell the truth. Suspending judgment helps you tell the truth about yourself. “The truth will set you free” is a saying that endures for a reason. The closer you get to the truth, the more powerful your discovery statements. If you notice that you are avoiding the truth, don’t blame yourself. Just tell the truth about it.
Planning for Success: Taking Actions Using Intention Statements
Intention statements can be used to alter your course. These statements are about your commitment to take action based on increased awareness. An intention arises out of your choice to direct your energy toward a specific task and to aim at a particular goal. The processes of discovery and intention reinforce each other.
Even simple changes in behavior can produce results. If you feel like procrastinating, then tackle just one small, specific task related to your intention. Find something you can complete in minutes or less, and do it now . For example, access just one website related to the topic of your next assigned paper. Spend just 3 minutes previewing a reading assignment. Taking baby steps like these can move you into action with grace and ease.
Make intentions positive. The purpose of writing intention statements is to focus on what you want rather than what you don’t want. Instead of writing, “I will not fall asleep while studying chemistry,” write, “I intend to stay awake when studying chemistry.” Also, avoid the word try . Trying is not doing. When we hedge our bets with try, we can always tell ourselves, “Well,
I tried to stay awake.”
Make intentions observable. Rather than writing, “I intend to work harder on my history assignments,” write, “I intend to review my class notes, and I intend to make summary sheets of my reading.”
Make intentions small and achievable. Break large goals into small, specific tasks that can be accomplished quickly. Small and simple changes in behavior—when practiced consistently over time—can have large and lasting effects.
When setting your goals, anticipate self-sabotage. Be aware of what you might do, consciously or unconsciously, to undermine your best intentions. Also, be careful with intentions that depend on other people. If you intend for your study group to complete an assignment by Monday, then your success depends on the students in the group. Likewise, you can support your group’s success by following through on your stated intentions.
Set time lines. For example, if you are assigned a paper to write, break the assignment into small tasks and set a precise due date for each one: “I intend to select a topic for my paper by 9:00 A.M. Wednesday.”
Move from intention to action. Intention statements are of little use until you act on them. If you want new results in your life, then take action. Life responds to what you do .
Planning for Success: Identifying and Changing Habits
Discovery leads to awareness. Intention leads to commitment, which naturally leads to focused action.
The processes of discovery, intention, and action create a dynamic and efficient cycle. First, you write discovery statements about where you are now. Second, you write intention statements about where you want to be and the specific steps you will take to get there. Finally, follow up with action—the sooner, the better. Then, start the cycle again. Write discovery statements about whether or how you act on your intention statements—and what you learn in the process. Follow up with more intention statements about what you will do differently in the future. Then, move into action and describe what happens next.
This process never ends. Each time you repeat the cycle, you get new results. It’s all about getting what you want and becoming more effective in everything you do. This is the path of mastery—a path that you can travel for the rest of your life.
Don’t panic when you fail to complete an intended task. Straying off course is normal. Simply make the necessary corrections. Consider the first word in the title of the textbook— becoming . This word implies that mastery is not an end state or final goal. Rather, mastery is a process that never ends.
Miraculous progress might not come immediately. Do not be concerned. Stay with the cycle. Give it time. Use discovery statements to get a clear view of your world. Then, use intention statements to direct your actions. Whenever you notice progress, record it.
It can take the same amount of energy to get what you don’t want in school as it takes to get what you do want. Sometimes getting what you don’t want takes even more effort.
Planning for Success: Thinking About Motivation
Motivation is an important part of being a successful student. There are at least two ways to think about motivation. One is that the terms self-discipline , willpower , and motivation describe something missing in ourselves. We use these words to explain another person’s success—or our own shortcomings: “If I were more motivated, I’d be more successful in school.”
The other approach to thinking about motivation is to stop assuming that motivation is mysterious, determined at birth, or hard to come by. Motivation could be something that you already possess—the ability to do a task even when you don’t feel like it. This is a habit that you can develop with practice.
Promise it. Motivation can come simply from being clear about your goals and acting on them. Say that you want to start a study group. You can commit yourself to inviting people and setting a time and place to meet. Promise your classmates that you’ll do this, and ask them to hold you accountable. Self-discipline, willpower, and motivation—none of these mysterious characteristics has to get in your way. Just make a promise and keep your word.
Befriend your discomfort. Once you’re aware of your discomfort, stay with it a few minutes longer. Don’t judge it as good or bad. Accepting discomfort robs it of power. It might still be there, but in time it can stop being a barrier for you. Discomfort can be a gift—an opportunity to do valuable work on yourself. On the other side of discomfort lies mastery.
Change your mind—and your body. You can also get past discomfort by planting new thoughts in your mind or changing your physical stance. For example, instead of slumping in a chair, sit up straight or stand up. Get physically active by taking a short walk. Notice what happens to your discomfort.
Work with your thoughts. Replace “I can’t stand this” with “I’ll feel great when this is done” or “Doing this will help me get something I want.”
Sweeten the task. Sometimes it’s just one aspect of a task that holds you back. You can stop procrastinating merely by changing that aspect. If distaste for your physical environment keeps you from studying, for example, then change that environment. Reading about social psychology might seem like a yawner when you’re alone in a dark corner of the house. Moving to a cheery, well-lit library can sweeten the task.
Turn up the pressure. Sometimes motivation is a luxury. Pretend that the due date for your project has been moved up 1 month, 1 week, or 1 day. Raising the stress level slightly can spur you into action. In that way, the issue of motivation seems beside the point, and meeting the due date moves to the forefront.
Turn down the pressure. The mere thought of starting a huge task can induce anxiety. To get past this feeling, turn down the pressure by taking baby steps. Divide a large project into small tasks. In 30 minutes or less, you could preview a book, create a rough outline for a paper, or solve two or three math problems. Careful planning can help you discover many such steps to make a big job doable.
Ask for support. Other people can become your allies in overcoming procrastination. For example, form a support group and declare what you intend to accomplish before each meeting. Then, ask members to hold you accountable. If you want to begin exercising regularly, ask another person to walk with you three times per week. People in support groups, ranging from Alcoholics Anonymous to Weight Watchers, know the power of this strategy.
Compare the payoffs with the costs. Skipping a reading assignment can give you time to go to the movies. However, you might be unprepared for class and have twice as much to read the following week. Maybe there is another way to get the payoff (going to the movies) without paying the cost (skipping the reading assignment). With some thoughtful weekly planning, you might choose to give up a few hours of television and end up with enough time to read the assignment and go to the movies.
Heed the message. Sometimes lack of motivation carries a message that’s worth heeding. An example is the student who majors in accounting but seizes every chance to be with children. His chronic reluctance to read accounting textbooks might not be a problem. Instead, it might reveal his desire to major in elementary education. His original career choice might have come from the belief that “real men don’t teach kindergarten.” In such cases, an apparent lack of motivation signals a deeper wisdom trying to get through.
Planning for Success: Maintaining a Positive Attitude
Visible measures of success—such as top grades and résumés filled with accomplishments— start with invisible assets called attitudes . Some attitudes will help you benefit from all the money and time you invest in higher education. Consider these examples: “Every course is worthwhile.” “I learn something from any instructor.” “The most important factors in the quality of my education are my own choices.”
Other attitudes will render your investment worthless: “This required class is a total waste of time.” “You can’t learn anything from some instructors.” “Success depends on luck more than anything else.” “I’ve never been good at school.”
You can change your attitudes through regular practice with affirmations and visualizations.
Affirm It
An affirmation is a statement describing what you want. The most effective affirmations are personal, positive, and written in the present tense.
To use affirmations, first determine what you want, and then describe yourself as if you already have it. To get what you want from your education, you could write, “I, Malika Jones, am a master student. I take full responsibility for my education. I learn with joy, and I use my experiences in each course to create the life that I want.”
If you decide that you want a wonderful job, you might write, “I, Peter Webster, have a wonderful job. I respect and love my colleagues, and they feel the same way about me. I look forward to going to work each day.”
Effective affirmations include detail. Use brand names, people’s names, and your own name. Involve all of your senses—sight, sound, smell, taste, and touch. Take a positive approach. Instead of saying, “I am not fat,” say, “I am slender.”
Once you have written an affirmation, repeat it. Practice saying it out loud several times a day.
Visualize It
Here’s one way to begin. Choose what you want to improve. Then, describe in writing what it would look like, sound like, and feel like to have that improvement in your life. If you are learning to play the piano, write down briefly what you would see, hear, and feel if you were playing skillfully. If you want to improve your relationships with your children, write down what you would see, hear, and feel if you were communicating with them successfully.
Once you have a sketch of what it would be like to be successful, practice seeing it in your mind’s eye. Whenever you toss the basketball, it swishes through the net. Every time you invite someone out on a date, the person says “yes.” Each test the teacher hands back to you is graded an A. Practice at least once a day. Then, wait for the results to unfold in your life.
Be clear about what you want, and then practice it.
Developing the Modes of Learning
As you have learned, one of the ways to think about your own learning process is to examine how you perceive and process information—your preferred learning mode. Each mode of learning represents a unique way of perceiving and processing:
- Concrete experience (feeling)
- Reflective observation (watching)
- Abstract conceptualization (thinking)
- Active experimentation (doing)
Although you may tend to favor one of the modes, developing all four modes offers many potential benefits. For example, you can excel in many types of courses and find more opportunities to learn outside the classroom. You can expand your options for declaring a major and choosing a career. You can also work more effectively with people who learn differently from you.
In addition, you’ll be able to learn from instructors no matter how they teach. Let go of statements such as “My teachers don’t get me” and “The instructor doesn’t teach to my learning style.” Replace those negative statements with more positive attitudes: “I am responsible for what I learn” and “I will master this subject by using several modes of learning.”
No matter which of these you’ve tended to prefer, you can develop the ability to use all four modes. You can explore new learning styles simply by adopting new habits related to each of these activities. Consider the following suggestions as places to start.
To Gain Concrete Experience (Feeling)
- See a live demonstration or performance related to your course content.
- Engage your emotions by reading a novel or seeing a video related to your course.
- Interview an expert in the subject you’re learning or a master practitioner of a skill you want to gain.
- Conduct role-plays, exercises, or games based on your courses.
- Conduct an informational interview with someone in your chosen career or “shadow” that person for a day on the job.
- Look for a part-time job, internship, or volunteer experience that complements what you do in class.
- Deepen your understanding of another culture and extend your foreign language skills by studying abroad.
To Gain More Reflective Observation (Watching)
- Keep a personal journal, and write about connections among your courses.
- Form a study group to discuss and debate topics related to your courses.
- Set up a website, blog, email listserv, or online chat room related to your major.
- Create analogies to make sense of concepts; for instance, see if you can find similarities between career planning and putting together a puzzle.
- Visit your course instructor during office hours to ask questions.
- During social gatherings with friends and relatives, briefly explain to them what your courses are about.
To Develop Abstract Conceptualization (Thinking)
- Take notes on your reading in outline form; consider using word-processing software with an outlining feature.
- Supplement assigned texts with other books, magazine and newspaper articles, and related websites.
- Attend lectures given by your current instructors and others who teach the same subjects.
- Take the ideas presented in text or lectures and translate them into visual form—tables, charts, diagrams, and maps.
- Create visuals and use computer software to recreate them with more complex graphics and animation.
To Gain More Active Experimentation (Doing)
- Conduct laboratory experiments or field observations.
- Go to settings where theories are being applied or tested.
- Make predictions based on theories you learn, and then see if events in your daily life confirm your predictions.
- Try out a new behavior described in a lecture or reading, and observe its consequences in your life.
The following chart identifies some of the natural talents people have, as well as challenges for people who have a strong preference for any one mode of learning. For example, if Mode 2 (Reflective Observation) is most like you, then look at the lower right-hand corner of the following chart to see whether it gives an accurate description of you.
Employing your Multiple Intelligences, Part 1
Gardner’s (1993) theory of multiple intelligences complements the discussion of different learning styles. The main point is that there are many ways to gain knowledge and acquire new behaviors. You can use Gardner’s concepts to explore a range of options for achieving success in school, work, and relationships.
The following list identifies each of the intelligences and describes the strategies you can use to develop more effective learning strategies. As you review each of the first three intelligences below, write down any of the characteristics that describe you. Also, identify learning strategies that you intend to use. Finally, note any of the possible careers that spark your interest.
Verbal/Linguistic
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Characteristics
- You enjoy writing letters, stories, and papers.
- You prefer to write directions rather than draw maps.
- You take excellent notes from textbooks and lectures.
- You enjoy reading, telling stories, and listening to them.
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Learning Strategies
- Highlight, underline, and write notes in your textbooks.
- Recite new ideas in your own words.
- Rewrite and edit your class notes.
- Talk to other people often about what you’re studying.
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Careers
- Librarian, lawyer, editor, journalist, English teacher, radio or television announcer
Mathematical/Logical
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Characteristics
- You enjoy solving puzzles.
- You prefer math or science class to English class.
- You want to know how and why things work.
- You make careful, step-by-step plans.
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Learning Strategies
- Analyze tasks so that you can order them in a sequence of steps.
- Group concepts into categories, and look for underlying patterns.
- Convert text into tables, charts, and graphs.
- Look for ways to quantify ideas—express them in numerical terms.
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Careers
- Accountant, auditor, tax preparer, mathematician, computer programmer, actuary, economist, math or science teacher
Visual/Spatial
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Characteristics
- You draw pictures to give an example or clarify an explanation.
- You understand maps and illustrations more readily than text.
- You assemble things from illustrated instructions.
- You especially enjoy books that have a lot of illustrations.
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Learning Strategies
- When taking notes, create concept maps, mind maps, and other visuals.
- Code your notes by using different colors to highlight main topics, major points, and key details.
- When your attention wanders, focus it by sketching or drawing.
- Before you try a new task, visualize yourself doing it well.
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Careers
- Architect, commercial artist, fine artist, graphic designer, photographer, interior decorator, engineer, cartographer
Reference
Gardner, Howard. Frames of Mind: The Theory of Multiple Intelligences. New York: Basic Books, 1993.
Employing your Multiple Intelligences, Part 2
Continue to review the next five multiple intelligences. Which intelligences seem to fit your learning preferences?
Bodily/Kinesthetic
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Characteristics
- You use a lot of gestures when talking.
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Learning Strategies
- Be active in ways that support concentration; for example, pace as you recite, read while standing up, and create flash cards.
- Carry materials with you, and practice studying in several different locations.
- Create hands-on activities related to key concepts; for example, create a game based on course content.
- Notice the sensations involved with learning something well.
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Careers
- Physical education teacher, athlete, athletic coach, physical therapist, chiropractor, massage therapist, yoga teacher, dancer, choreographer, actor
Musical/Rhythmic
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Characteristics
- You often sing in the car or shower.
- You easily tap your foot to the beat of a song.
- You play a musical instrument.
- You feel most engaged and productive when music is playing.
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Learning Strategies
- During a study break, play music or dance to restore energy.
- Put on background music that enhances your concentration while studying.
- Relate key concepts to songs you know.
- Write your own songs based on course content.
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Careers
- Professional musician, music teacher, music therapist, choral director, musical instrument sales representative, musical instrument maker, piano tuner
Intrapersonal
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Characteristics
- You enjoy writing in a journal and being alone with your thoughts.
- You think a lot about what you want in the future.
- You prefer to work on individual projects over group projects.
- You take time to think things through before talking or taking action.
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Learning Strategies
- Connect course content to your personal values and goals.
- Study a topic alone before attending a study group.
- Connect readings and lectures to a strong feeling or significant past experience.
- Keep a journal that relates your course work to events in your daily life.
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Careers
- Minister, priest, rabbi, professor of philosophy or religion, counseling psychologist, creator of a home-based or small business
Interpersonal
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Characteristics
- You enjoy group work over working alone.
- You have plenty of friends and regularly spend time with them.
- You prefer talking and listening over reading or writing.
- You thrive in positions of leadership.
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Learning Strategies
- Form and conduct study groups early in the term.
- Create flash cards, and use them to quiz study partners.
- Volunteer to give a speech or lead group presentations on course topics.
- Teach the topic you’re studying to someone else.
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Careers
- Manager, school administrator, salesperson, teacher, counseling psychologist, arbitrator, police officer, nurse, travel agent, public relations specialist, creator of a midsize to large business
Naturalistic
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Characteristics
- As a child, you enjoyed collecting insects, leaves, or other natural objects.
- You enjoy being outdoors.
- You find that important insights occur during times you spend in nature.
- You read books and magazines on nature-related topics.
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Learning Strategies
- During study breaks, take walks outside.
- Post pictures of outdoor scenes where you study, and play recordings of outdoor sounds while you read.
- Invite classmates to discuss course work while taking a hike or going on a camping trip.
- Focus on careers that hold the potential for working outdoors.
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Careers
- Environmental activist, park ranger, recreation supervisor, historian, museum curator, biologist, criminologist, mechanic, woodworker, construction worker, construction contractor or estimator
Remember this is not an exhaustive list or a formal inventory. Take what you find merely as a starting point to developing your learning strategies. You can invent strategies of your own to cultivate different intelligences.
 As you review the following suggestions, think about which study methods you already use. You might consider trying one of these suggestions to support your individual learning preference or try a new method to enhance another learning style.
Enhancing Visual Learning
- Preview reading assignments by looking for elements that are highlighted visually—bold headlines, charts, graphs, illustrations, and photographs.
- When taking notes in class, leave plenty of room to later add your own charts, diagrams, tables, and other visuals.
- Whenever an instructor writes information on a blackboard or overhead display, copy it exactly in your notes.
- Transfer your handwritten notes to your computer. Use word-processing software that allows you to format your notes in lists, add headings in different fonts, and create visuals in color.
- Before you begin an exam, quickly sketch a diagram on scratch paper. Use this diagram to summarize the key formulas or facts you want to remember.
- During tests, see whether you can visualize pages from your handwritten notes or images from your computer-based notes.
Enhancing Auditory Learning
- Reinforce memory of your notes and readings by talking about them. When studying, stop often to recite key points and examples in your own words.
- After reciting several summaries of key points and examples, record your favorite version or write it out.
- Read difficult passages in your textbooks slowly and out loud.
- Join study groups, and create short presentations about course topics.
- Visit your instructors during office hours to ask questions.
Enhancing Kinesthetic Learning
- Look for ways to translate course content into 3D models that you can build. While studying biology, for example, create a model of a human cell using different colors of clay.
- Supplement lectures with trips to museums, field observations, lab sessions, tutorials, and other hands-on activities.
- Recite key concepts from your courses while you walk or exercise.
- Intentionally set up situations in which you can learn by trial and error.
- Create a practice test, and write out the answers in the room where you will actually take the exam.
One variation of the VAK system has been called VARK (Fleming 2012). The R describes a preference for learning by reading and writing. People with this preference might benefit from translating charts and diagrams into statements, taking notes in lists, and converting those lists into possible items on a multiple-choice test.
Reference
Fleming, Neil. 2012. “VARK: A Guide to Learning Styles.” Accessed November 8, 2012. www.vark-learn.com/.


19.10: Searching Arrays
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Overview
Linear search or sequential search is a method for finding a target value within a list. It sequentially checks each element of the list for the target value until a match is found or until all the elements have been searched. [1]
Discussion
Finding a specific member of an array means searching the array until the member is found. It’s possible that the member does not exist and the programmer must handle that possibility within the logic of his or her algorithm.
“The linear search is a very simple algorithm. Sometimes called a sequential search, it uses a loop to sequentially step through an array, starting with the first element. It compares each element with the value being searched for, and stops when either the value is found or the end of the array is encountered. If the value being searched for is not in the array, the algorithm will search to the end of the array.” [2]
Two specific linear searches can be made for the maximum (largest) value in the array or the minimum (smallest) value in the array. Maximum and minimum are also known as max and min. Note that the following max and min functions assume an array size >= 1.
Pseudocode
Function Main Declare Integer Array ages[5] Declare Integer maximum Declare Integer minimum Assign ages = [49, 48, 26, 19, 16] Assign maximum = max(ages) Assign minimum = min(ages) Output "Maximum age is: " & maximum Output "Minimum age is: " & minimum End Function max (Integer Array array) Declare Integer maximum Declare Integer index Assign maximum = array[0] For index = 1 to Size(array) - 1 If maximum < array[index] Assign maximum = array[index] End End Return Integer maximum Function min (Integer Array array) Declare Integer minimum Declare Integer index Assign minimum = array[0] For index = 1 to Size(array) - 1 If minimum > array[index] Assign minimum = array[index] End End Return Integer minimum
Output
Maximum age is: 49 Minimum age is: 16
Key Terms
- linear search
- Using a loop to sequentially step through an array.
- maximum
- Aka max or the largest member of an array.
- minimum
- Aka min or the smallest member of an array.
References
- cnx.org: Programming Fundamentals – A Modular Structured Approach using C++
- Wikiversity: Computer Programming


15.1: Composition of Blood
You have probably had blood drawn from a superficial vein in your arm, which was then sent to a lab for analysis. Some of the most common blood tests—for instance, those measuring lipid or glucose levels in plasma—determine which substances are present within blood and in what quantities. Other blood tests check for the composition of the blood itself, including the quantities and types of formed elements.
One such test, called a hematocrit , measures the percentage of RBCs, clinically known as erythrocytes, in a blood sample. It is performed by spinning the blood sample in a specialized centrifuge, a process that causes the heavier elements suspended within the blood sample to separate from the lightweight, liquid plasma ( Figure 15.1 ). Because the heaviest elements in blood are the erythrocytes, these settle at the very bottom of the hematocrit tube. Located above the erythrocytes is a pale, thin layer composed of the remaining formed elements of blood. These are the WBCs, clinically known as leukocytes, and the platelets, cell fragments also called thrombocytes. This layer is referred to as the buffy coat because of its color; it normally constitutes less than 1 percent of a blood sample. Above the buffy coat is the blood plasma, normally a pale, straw- colored fluid, which constitutes the remainder of the sample.
The volume of erythrocytes after centrifugation is also commonly referred to as packed cell volume (PCV) . In normal blood, about 45 percent of a sample is erythrocytes. The hematocrit of any one sample can vary significantly, however, about 36–50 percent, according to gender and other factors. Normal hematocrit values for females range from 37 to 47, with a mean value of 41; for males, hematocrit ranges from 42 to 52, with a mean of 47. The percentage of other formed elements, the WBCs and platelets, is extremely small so it is not normally considered with the hematocrit. So the mean plasma percentage is the percent of blood that is not erythrocytes: for females, it is approximately 59 (or 100 minus 41), and for males, it is approximately 53 (or 100 minus 47).